21-Spline 4WD Gearbox Coupling for International Harvester Tractors SKU: QT4972

When your 4WD coupling fails or shows excessive wear, you lose critical front wheel drive engagement just when traction matters most. This 21-spline coupling restores reliable power transfer from your gearbox to the front axle, eliminating slippage and getting your International Harvester back to full 4WD performance on steep terrain or in muddy field conditions.

Why Genuine Performance Matters

• Precision-machined 21 splines ensure full engagement without excessive play that causes rapid wear
• Heavy-duty steel construction withstands high torque loads and sudden engagement forces
• Heat-treated splines resist wear and maintain positive engagement under demanding field conditions
• Exact-fit design eliminates guesswork and provides years of reliable service

4WD driveline components face extreme stress from sudden engagement loads, torque multiplication through the transmission, and the shock forces of implement operation. This coupling handles these demanding conditions with precision manufacturing that maintains proper clearances and smooth operation throughout its service life. When installing, ensure proper alignment to prevent binding and verify that the coupling slides smoothly onto the splines without forcing.